Swift syntax: lazy -

today saw code confused me:

lazy var variable ＝ {......}() 

i hope can explain me usage of lazy.

lazy var variable: class ＝ {    <initialisation>    return <resulting object> }() 

is equivalent to:

var _variable: class? var variable: class {     get{         if _variable == nil {             <initialisation>             _variable = <resulting object>         }          return _variable!     } } 

in short: initialises object when needed